Help me understand iPXE code

[Rickert]

In main.c, it calls initialize() and startup(). Inside each of these functions, it loops through table that contains the registered functions and calls them:

Code:

void startup ( void ) {
    struct startup_fn *startup_fn;

    if ( started )
        return;

    /* Call registered startup functions */
    for_each_table_entry ( startup_fn, STARTUP_FNS ) {
        if ( startup_fn->startup )
            startup_fn->startup();
    }

    started = 1;
}

I don't know where the registered functions are.

STARTUP_FNS:

Code:

#define STARTUP_FNS __table ( struct startup_fn, "startup_fns" )

__table:

Code:

#define __table( type, name ) ( type, name )

__table is the end of what I can look into. The comment says that it "Declare a linker table". But how can it get the functions?

Please help. I really want to understand. Thanks.